Serum alkaline phosphatase is a prognostic marker in bone metastatic disease of the extremity.

Purpose: The purpose of this study was to determine the prognostic value of serum alkaline phosphatase for treatment decision making in metastatic bone disease.

Methods: 1090 patients who underwent surgery for extremity metastatic disease were retrospectively identified at two tertiary care centers. The association between alkaline phosphatase and mortality was assessed by bivariate and multivariate analyses.

Risk adjustment of mental health and substance abuse payments.

This study used 1992 and 1993 data from private employers to compare the performance of various risk adjustment methods in predicting the mental health and substance abuse expenditures of a nonelderly insured population. The methods considered included a basic demographic model, Ambulatory Care Groups, modified Ambulatory Diagnostic Groups and Hierarchical Coexisting Conditions (a modification of Diagnostic Cost Groups), as well as a model developed in this paper to tailor risk adjustment to the unique characteristics of psychiatric disorders (the "comorbidity" model). Our primary concern was the amount of unexplained systematic risk and its relationship to the likelihood of a health plan experiencing extraordinary profits or losses stemming from enrollee selection.

How well do ambulatory care groups predict expenditures on mental health and substance abuse patients?

This paper evaluates the ability of Ambulatory Care Groups (ACGs) to prospectively predict mental health and substance abuse expenditures and total health care expenditures of persons enrolled in the New Hampshire Medicaid Program during fiscal years 1993 and 1994. A series of multi-part models is estimated separately for adults and children and a synthetic R-squared and the mean absolute predictive error are calculated. The results show that with the exception of predicting total expenditures for children, ACGs do not perform as well as simple models containing various demographic and prior mental health/substance abuse utilization measures.

Effect of distance, aggregation, and habitat on levels of seed predation for two mammal - dispersed neotropical rain forest tree species.

The effect of seed aggregation and distance from conspecific trees on seed predation was experimentally examined for two neotropical tree species, Macoubea guianensis (Apocynaceae) and Pouteria sp. (Sapotaceae) in a lowland tropical rain forest in northeastern Peru. Results of these experiments are discussed in the context of the Janzen-Connell model (Janzen 1970; Connell 1971), which predicts decreased seed survival near parent trees due to either density-or distance-responsive mortality, and Howe's model (Howe 1989) which predicts that trees with seeds dispersed in clumps (aggregated) will not suffer density-dependent predation, and will have higher survival of seeds near the parent tree than other trees.